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Interrater and test-retest reliability of the Hand Assessment for Infants
Anna Ullenhag1,2, Linda Ek1, Ann-Christin Eliasson1
1Neuropediatric Unit, Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.
Insights
The Hand Assessment for Infants (HAI) demonstrates excellent reliability for assessing infant hand function. Smallest detectable differences (SDD) of 2-3 HAI units indicate true changes in hand function for infants with unilateral cerebral palsy.
Area of Science:
- Pediatric occupational therapy
- Neurodevelopmental assessment
- Infant motor function
Background:
- Reliable assessment tools are crucial for tracking developmental progress in infants.
- The Hand Assessment for Infants (HAI) is used to evaluate hand function in infants.
- Understanding the measurement properties of the HAI is essential for its clinical and research applications.
Purpose of the Study:
- To evaluate the interrater and test-retest reliability of the Hand Assessment for Infants (HAI).
- To determine the standard error of measurement (SEM) and smallest detectable difference (SDD) for the HAI.
- To establish the reliability and measurement error of the HAI in infants, including those with unilateral cerebral palsy.
Main Methods:
- Video-recorded HAI play sessions of 55 infants (3-11 months) were independently scored by three experienced occupational therapists.
- The study included typically developing infants and those with clinical signs of unilateral cerebral palsy.
- Intraclass correlation coefficients (ICC), Bland-Altman plots, SEM, and SDD were calculated to assess reliability and measurement error.
Main Results:
- Excellent interrater and test-retest reliability was found for the Both Hands Measure (BoHM) and Each Hand Sum score (EaHS) (ICCs 0.96-0.99).
- Individual item reliability ranged from good to excellent (ICCs 0.81-0.99).
- The smallest detectable difference (SDD) was 2 HAI units for the EaHS and 3 HAI units for the BoHM in infants with unilateral CP.
Conclusions:
- The Hand Assessment for Infants (HAI) demonstrates good to excellent reliability, supporting its use in clinical practice and research.
- Low SDD values indicate that changes beyond these thresholds represent true changes in infant hand function.
- A change of 3 or more HAI units is considered a true change, signifying meaningful improvement or decline in hand function.
Aim:
To evaluate the interrater and test-retest reliability, standard error of measurement (SEM), and the smallest detectable difference (SDD) of the Hand Assessment for Infants (HAI).
Method:
HAI assessments of 55 infants (26 females, 29 males), 25 with clinical signs of unilateral cerebral palsy (CP) and 30 typically developing (mean [SD] age 6.8mo [2.4], range 3-11mo), were scored individually by three therapists. Three clinically experienced occupational therapists (OT 1-OT 3) with extensive experience in using the HAI, independently scored the video recorded HAI play sessions. Analysis of the combined group of infants and just the infants with clinical signs of unilateral CP (12 females, 13 males; mean age 7.6mo [2.1]) were conducted. Intraclass correlation coefficients (ICC, 2.1), Bland-Altman plots, SEM, and SDD were calculated.
Results:
Interrater and test-retest reliability were excellent for the Both Hands Measure (BoHM) and the Each Hand Sum score (EaHS), with ICCs of 0.96 to 0.99. For individual items, the interrater and test-retest reliability was good to excellent (ICC 0.81-0.99). The SDD for the EaHS was 2 points, and for the BoHM the SDD it was 3 HAI units for infants with signs of unilateral CP.
Interpretation:
The HAI results showed good to excellent reliability. The SDDs were low, indicating that results beyond these levels exceed the measurement error and, thus, can be considered true changes. What this study adds The Hand Assessment for Infants (HAI) shows excellent reliability. A change of ≥3 HAI units is considered a true change. The HAI yields reliable measures for research and clinical practice.
